Biomechanical analysis on the shock attenuation in normal walking of different-pattern old social dancing exercises / 中国组织工程研究

ABSTRACT

BACKGROUND: People, with various live patterns, have different impacts when walking, while the impact type always takes effects on shock attenuation of people. Foreign researches had shown shock attenuation during walking had been linked to many kinds of injuries.OBJECTIVE: This study aimed to examine whether dancers with different dancing patterns would show different impact shock attenuation when walking.DESIGN: A controlled observation.SETTING: Sports College, Guangxi Normal University; College of Human Movement Science, Beijing Sports University.PARTICIPANTS: Fourteen old social dancing exercisers who had 3 years of dancing exercises and exercised 1.0-2.0 hours per day were selected from family members' area of Beijing Sports University and recruited for this study. Seven subjects dancing with smooth rises and falls were selected into one group (namely group A) by a professional social dance teacher and another seven retires dancing with abrupt rises and falls were selected into another group (namely group B). The age, body height and body mass of subjects between two groups could be comparable. METHODS: The BK4393 uni-gain miniature accelerometers (Denmark) were attached to the skin of 3 cm below the tubercle of tibia and median line of frontal bone in subjects to test their the impact acceleration during normal speed. At the same time, retires' gaits were filmed by a normal speed camera to get the kinematic variables. All variables related to shock attenuation were compared by statistical means, and the difference of shock attenuation between two groups were analyzed.MAIN OUTCOME MEASURES: Related extremity gait kinematic parameters, peak acceleration of tibia and head, and impact shock attenuation during normal walkingRESULTS: Fourteen subjects participated in the finial analysis. Group B showed significant higher values of the maximum knee angle, maximum ankle angle and total angle change of ankle joint statistically than group A (P ＜ 0.05). There were no significant differences in impact acceleration of tibia stance phase between two groups (P ＞ 0.05), impact acceleration of head in the group A was lower than that in the group B (P ＜ 0.05), and shock attenuation between tibia and head was better in the group A than in the group B (P =0.007). CONCLUSION: Dancing with smooth rises and falls is beneficial to enhancing shock attenuation ability and improving ankle dorsiflexion control and the whole coordinated ability in social dancing exercises.